I I 12 rAR!<M:YSTA 



solid ; pseudocardinals ragged : laterals split, sometime? into 

 three divisions in each valve ; beak cavities very deep, com- 

 pressed ; muscle scars deep ; nacre silvery. 

 Length 50, height 38. diam. 22 mm. 

 Burma. 

 Unio bhainocusis Theop.ald, Jl. As. Soc. Beng., XLII, 1874, 

 Pt. 2. p. 207, pi. XVII, fig. I. — PHanley and Theobald, 

 Conch. Ind.. 1876, p. 62, pi. ci.v. fig. 2. — von Martens, 

 Arch, fijr Naturf., 1899, p. 38, pi. v, figs. 2-4. 

 Parreysia hhamoensis Simpson, Syn., 1900, p. 843. 



A solid, triangular species. I have before me a right valve 

 of a shell, which agrees almost absolutely with the figure in 

 the Conchologia Indica, but is not quite so strongly corrugated 

 behind. The beak cavit}- is very deep and compressed, the 

 muscle scars are small and deep and the nacre is brilliant. 



Parreysi.a. MANDELAYENSis (Theobald). 



• Shell decidedly triangular, rather solid, subinflated, beaks 

 and umbonal region much elevated, strongly sculptured with 

 zigzag-radial bars, sometimes with one or two radial rows of 

 tubercles, the sculpture being continued over the whole shell ; 

 posterior ridge narrowly rounded, placed close to the lightly 

 curved post-dorsal outline : anterior end abliquely subtruncate 

 above, rounded below ; base line rounded ; surface having 

 strong, uneven, concentric sculpture ; epidermis tawny to 

 greenish, sul:)shining : pseudocardinals subtriangular, not very 

 ragged ; anterior nmscle scars deep ; beak cavities deep ; nacre 

 bluish-white. 



Length 40, height 31, diam. 21 mm. 



Mandelay. 

 Un'w mandelaycnsis Theobald, Jl. As. Soc. Beng., XLTL 



1874, p. 208, pi. xviT, fig. 2. — Hanley' and Theobald, Conch. 



Ind., 1876. p. 62, pi. CLiv, fig. 4. 

 Parreysia hhamoensis. (part), Simpson, Syn., 1900, p. 843. 



Tn the Synopsis T placed this in the Synonymy of P. hhamo- 

 ensis, but T am satisfied that this was an error. Since writing 

 that T have seen several shells, which agree fairlv well with 



